State Key Laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, China; Chongqing Key Laboratory of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, China.
State Key Laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, China; Chongqing Key Laboratory of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, China.
Colloids Surf B Biointerfaces. 2020 May;189:110828. doi: 10.1016/j.colsurfb.2020.110828. Epub 2020 Jan 31.
Lipid vesicle is spherical membranous structure with a concave surface on the inside. When a beam of light illuminates a lipid vesicle, the light reflected from the vesicular concave membrane can be focused to have higher intensity and generate enhanced effects. By observing and simulating light reflected from giant unilamellar vesicles (GUVs), the intensity distribution of the light reflected from a spherical concave lipid membrane was investigated. The reflected light had focused characteristics. Its intensity was concentrated 10,000 times and even exceeded the intensity of incident light in a confined region, creating another effective light source in the lipid vesicle. The fluorescence quenching of sulfo-Cy5 encapsulated in spherical GUVs was stronger than that of the outside solution when irradiated by a 632.8 nm laser. When irradiated with ultraviolet light C (UVC), the damage to plasmid DNA encapsulated with spherical GUVs was greater than that of pure plasmid DNA solution and plasmid DNA mixed with lipid membrane fragments. Therefore, in addition to the effects of incident light, the focused light reflected from GUVs could generate incremental effects on encapsulated photoreactive materials if the spherical structure of the lipid membrane was maintained. These results proved that concave lipid membranes of spherical vesicles can focus light and utilize it to generate enhanced effects. The capability of light focusing and its influence on DNA may provide new insights for understanding the function of lipid membranes in cellular life.
脂质体是一种具有内凹表面的球形膜结构。当一束光照射脂质体时，从囊泡凹面膜反射的光可以聚焦，从而具有更高的强度并产生增强效应。通过观察和模拟巨大单层囊泡（GUV）中光的反射，可以研究从球形凹面脂质膜反射的光的强度分布。反射光具有聚焦特性，其强度集中了 10000 倍，甚至在受限区域内超过了入射光的强度，在脂质体中创造了另一个有效的光源。当用 632.8nm 激光照射时，包裹在球形 GUV 中的 sulfo-Cy5 的荧光猝灭比外部溶液更强。用紫外线 C（UVC）照射时，包裹在球形 GUV 中的质粒 DNA 的损伤大于纯质粒 DNA 溶液和与脂质膜碎片混合的质粒 DNA。因此，除了入射光的影响外，如果脂质膜的球形结构得以维持，从 GUV 反射的聚焦光还可以对封装的光反应性材料产生增量效应。这些结果证明，球形囊泡的凹面脂质膜可以聚焦光并利用其产生增强效应。光聚焦的能力及其对 DNA 的影响可能为理解脂质膜在细胞生命中的功能提供新的见解。
